The proposal of “Urbamedia” is to undertake the development of  3D virtual and interactive models of historical areas of Latin-American cities. The selected zone is the “Mayo Avenuei  including the “Mayo Square”, an historical place of the city of Buenos Aires, Argentina, this project is financed by the National Agency of  Scientific and Technological Development of Argentina and the University of Buenos Aires.We are presenting  the first experimental model of the “Mayo Squarei that has been developed at  ABACUS, Department of Architecture & Building Aids Computer Unit, University of Strathclyde UK. combined with a system analysis of urban activities using the “Atlas.ti” CAQDAS software.This particular use of  the “Atlas.ti” software is under experimental applications to this type of urban analysis procedures, allowed  us the possibility to analysed a set of activities  by means of graph theory as result of a series of interviews  to the people working in the area. We are also looking to include historical areas of three cities: Mar del Plata, Rosario and Santa Fe (Argentina) and eventually other cities from Latin América as Rio de Janeiro and Habana.Due that ABACUS has a strong experience in city modelling plus the powerful software and hardware used there, we must develop a VRML customized menu to be adapted to our low cost PC equipment. The 3D model will be used mainly in urban design simulation procedures and the idea is to extend to other type of simulations of the environmental parameters.